The present invention relates to a lubricating apparatus for an engine or engine unit of, for example, an outboard motor, incorporating an oil pump for pumping oil accumulated in an oil pan disposed to a lower portion of the engine to supply an oil to the inside portion of the engine.
FIG. 7 is a vertical sectional view showing a usual example of a lubricating apparatus for an outboard motor. A lubricating apparatus 100 is provided with an oil pan 101 disposed in the lower portion of an engine (not shown) in a state of an outboard motor mounted to a hull, for example. An oil strainer section 104 is disposed at a lowermost end of a metallic oil suction pipe 103 extending from an oil pump (not shown) disposed in the lower portion of the engine to the bottom of the oil pan 101, i.e. an oil accumulating tank 102.
When the oil pump of the lubricating apparatus 100 is operated owning to the operation of the engine, the oil in the oil accumulating tank 102 is strained or filtered by the oil strainer section 104. The oil then passes through the oil suction pipe 103 and is sucked by the oil pump so as to be, under pressure, supplied to the inside portion of the engine.
The lubricating apparatus 100 structured as described above incorporates the oil strainer section 104 having a large diameter and disposed in the bottom portion of the oil accumulating tank 102. Therefore, a sufficiently large clearance must be provided between the oil strainer section 104 and an inner wall 112 of the oil pan 101, as shown in FIG. 8. Therefore, the area of the bottom of the oil accumulating tank 102 has been enlarged.
An outboard motor designed such that side cross sectional area of the lower portion of the oil pan 101 is reduced. However, in such design, there occurs a difficulty in enlarging the area of the bottom of the oil accumulating tank 102. Therefore, the oil strainer section 104 cannot easily be mounted. When the oil pan 101 is mounted to or removed from the engine unit, there is a fear that the oil strainer section 104 collides with the oil pan 101 and is hence damaged.